What Is a T Cell Count?
A T cell count is a blood test that measures the number of T cells in your body. A T cell is a type of white blood cell. White blood cells are also called lymphocytes. These cells fight off diseases. The two categories of lymphocytes are T cells and B cells. The T cells respond to viral infections, while the B cells fight bacterial infections. Your body sometimes has too many or too few T cells. This may be a sign that your immune system isn’t functioning properly.
A T cell count may also be known as a thymus-derived lymphocyte count, or a T lymphocyte count.
If you’re being treated for HIV, this test may be known as a CD4 cell count. Some T cells contain a CD4 receptor. This receptor is where HIV attaches to the T cell. When the number of CD4 T cells drops below a certain point, it may be time for you to begin treatment for HIV and AIDS.